A photodiode (PD) receives an optical signal and converts the optical signal into an electrical signal. A transimpedance amplifier (TIA), which converts a current signal output from the PD into a voltage signal, is coupled to the PD.
The related art is disclosed in, for example, Zhenghao Lu, Kiat Seng Yeo, Jianguo Ma, Manh Anh Do, Wei Meng Lim, and Xueying Chen, “Broad-Band Design Techniques for Transimpedance Amplifiers”, IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS, vol. 54, No. 3, pp. 590-600, 2007.
However, in the related art described above, it is difficult to shorten a bonding wire between the PD and the TIA. Thus, the distance between the PD and the TIA is made long and the size of the circuit is made large.